350 SOME OTHEtt HISTOLOGICAL METHODS. 



TOISON (Jowrn. Sci. med. de Lille, fev., 1885; Zeit. f. wiss. 

 Mik., 1885, p. 398) recommends that blood be mixed with the 

 following fluid : 



Distilled water 160 c.c. 



Glycerin (neutral, 30 Beaume) . 30 c.c. 



Pure sulphate of sodium ... 8 grammes. 



Pure chloride of sodium ... 1 gramme. 



Methyl-violet 5B 0'25 



(The methyl-violet is to be dissolved in the glycerin with 

 one half of the water added to it; the two salts are to be dis- 

 solved in the other half of the water ; and the two solutions 

 are to be mixed and filtered.) White blood-corpuscles stain 

 in this medium in five or ten minutes; the maximum of 

 coloration is attained in from twenty to thirty minutes. 

 White blood-corpuscles, violet; red blood-corpuscles, greenish. 



694. Demonstration of Blood-plates of Bizzozero (KEMP, Studies 

 fr. the Biol. Lab. Johns Hopkins Univ., May, 1886, iii, No. 6 ; 

 Nature, 1886, p. 132). The mere demonstration of the blood- 

 plates of Bizzozero is easy enough. A somewhat large drop 

 of blood is placed on a slide, and quickly washed with a small 

 stream of normal salt solution. The blood-plates are not 

 washed away, because they have the property of adhering to 

 glass ; and on bringing the slide under the microscope they 

 will be seen in large numbers. If it be desired to make 

 permanent preparations of them, they should first be fixed. 

 This is done by putting a drop of osmic acid solution on the 

 finger before pricking it. 



695. BIONDI'S Section Method for Blood (Arch.f. mik. Anat., xxxi, 

 1888, p. 103). None of the foregoing methods are perfectly satisfactory as 

 regards the preservation of the elements of blood without deformation, and 

 at the same time in a perfectly permanent manner. Biondi's ingenious pro- 

 cess does this. 



Blood is fixed with osmic acid solution as described above, 692. Four 

 or five drops of the mixture of blood and osmium solution are then mixed 

 with agar-agar jelly melted at 35 to 37 C. The whole is allowed to cool, 

 and the mass is put to harden in alcohol of 85 per cent. After a few days 

 the mass will have attained a consistence that allows of its being imbedded 

 in pith and cut with a microtome. The sections are treated according to 

 UK> usual methods. The best stains are obtained with methyl-green, 

 methylen-blue, fuchsin, and safrunin. Methyl-green and eosin is also a 

 -no.l combination. After staining the sections are cleared and mounted in 

 balsam in the usual way. 



